Extruded Polystyrene (XPS) Home Extruded Polystyrene (XPS) Extruded Polystyrene (XPS) is a rigid, closed-cell foam insulation board manufactured through a continuous extrusion process using polystyrene resin combined with a blowing agent. Unlike EPS, which is formed from fused, expanded beads, XPS features a uniform, closed-cell structure without bead boundaries — giving it greater compressive strength, […]